miR-129 Promotes the Proliferation of Alzheimer’s Neuronal Cells by Binding the 3′ Untranslated Regions (3′ UTR) of Amyloid Precursor Protein (APP)

Alzheimer’s disease (AD) is a neurodegenerative disease with memory loss and cognitive impairment. Short non-coding RNAs (miRNAs) are potential biomarkers and therapeutic targets for AD. This study aims to investigate miR-129’s role in AD. miR-129 and amyloid precursor protein (APP) expression was measured by Q-PCR, and LC3, p62, ATG5, Bcl-2, p-Tau and Caspase3 protein was detected by Western blot. Hydrogenase kits and DCFH-DA detected cell apoptosis, cytotoxicity and ROS generation. The interaction between APP and miR-129 was assessed by luciferase report experiment. HE staining and TUNEL assay evaluated hippocampal neuron damage. In AD patient serum, AD transgenic (TG) mouse brain tissue, and AB1-42-treated SH-SY5Y cells, miR-129 was downregulated but autophagy was increased. Overexpression of miR-129 reduced cell damage induced by AB1-42, and miR-129 can directly regulate APP expression by binding APP 3′-UTR. miR-129 inhibitors reversed the protective effect of shAPP on AB1-42-induced cell damage. In addition, miR-129 overexpression reduced neuronal damage through inhibiting autophagy in vivo. APP expression in AD patient and AD cell model was significantly increased compared to controls. Aβ-42 treatment caused up-regulation of APP expression, while APP knockdown inhibited neurons through autophagy. In conclusion, miR-129 overexpression can regulate autophagy by targeting APP5, thereby reducing neuronal damage in AD. These findings provide a new perspective for treating AD.

Polydatin Attenuates Cisplatin-Induced Acute Kidney Injury by Inhibiting Ferroptosis

Cisplatin is widely used in the treatment of solid tumors, but its application is greatly limited due to its nephrotoxicity; thus, there is still no effective medicine for the treatment of cisplatin-induced acute kidney injury (Cis-AKI). We previously identified that polydatin (PD) exerts nephroprotective effects by antioxidative stress in AKI models. Recent evidence suggests that oxidative stress-induced molecular events overlap with the process of ferroptosis and that there are common molecular targets, such as glutathione (GSH) depletion and lipid peroxidation. Nevertheless, whether the nephroprotective effect of PD is related to anti-ferroptosis remains unclear. In this study, the inhibitory effect of PD on ferroptosis was observed in both cisplatin-treated HK-2 cells (20 μM) in vitro and a Cis-AKI mouse model (20 mg/kg, intraperitoneally) in vivo, characterized by the reversion of excessive intracellular free iron accumulation and reactive oxygen species (ROS) generation, a decrease in malondialdehyde (MDA) content and GSH depletion, and an increase in glutathione peroxidase-4 (GPx4) activity. Remarkably, PD dose-dependently alleviated cell death induced by the system Xc− inhibitor erastin (10 μM), and the effect of the 40 μM dose of PD was more obvious than that of ferrostatin-1 (1 μM) and deferoxamine (DFO, 100 μM), classical ferroptosis inhibitors. Our results provide insight into nephroprotection with PD in Cis-AKI by inhibiting ferroptosis via maintenance of the system Xc−-GSH-GPx4 axis and iron metabolism.

Silica-Supported Assemblage of CuII Ions with Carbon Dots for Self-Boosting and Glutathione-Induced ROS Generation

The present work introduces coordinative binding of CuII ions with both amino-functionalized silica nanoparticles (SNs) and green-emitting carbon dots (CDs) as the pregrequisite for the CuII-assisted self-assembly of the CDs at the surface of the SNs. The produced composite SNs exhibit stable in time stimuli-responsive green fluorescence derived from the CuII-assisted assemblage of CDs. The fluorescence response of the composite SNs is sensitive to the complex formation with glutathione (GSH), enabling them to detect it with the lower limit of detection of 0.15 μM. The spin-trap-facilitated electron spin resonance technique indicated that the composite SNs are capable of self-boosting generation of ROS due to CuII→CuI reduction by carbon in low oxidation states as a part of the CDs. The intensity of the ESR signals is enhanced under the heating to 38 °C. The intensity is suppressed at the GSH concentration of 0.35 mM but is enhanced at 1.0 mM of glutathione, while it is suppressed once more at the highest intracellular concentration level of GSH (10 mM). These tendencies reveal the concentrations optimal for the scavenger or reductive potential of GSH. Flow cytometry and fluorescence and confocal microscopy methods revealed efficient cell internalization of SNs-NH2-CuII-CDs comparable with that of “free” CDs.

High Fructose Negatively Impacts Proliferation of NSC-34 Motor Neuron Cell Line

Objectives The main aim of this study is to identify the deleterious effects of indiscriminately consumed high fructose on motor neurons that are critically affected in many neurological conditions causing movement disorders including paralysis. Materials and Methods Neuroblastoma x mouse spinal cord motor neuron cell line (NSC-34) motor neuron cell lines were treated with high fructose and oxygen supplementation (18.8%) and assayed for cell proliferation/death, reactive oxygen species (ROS) generation, and oxidative stress response induction Statistical Analysis Mean and standard deviation, significance with and without high fructose (F)-5%, were estimated by t-tests using GraphPad Prism ver. 8.2.1 Results F-5% along with O2 (18.8%) annihilates the cells (∼85%) by day10 and inhibits cell division as observed by the presence of multinucleated cells. Unexpectedly, 1 to 2% of cells that survived, differentiated and displayed progressive neurite extension. Though not healthy, they were viable up to 80 days. F-5% increased ROS levels (∼34%) not accompanied by concomitant enhanced expression of oxidative stress response regulator, the transcription factor, nrf-2, or downstream effector, sod-1. Conclusion High fructose is extremely harmful to NSC-34 motor neuron cell line.

Acidic Tumor Microenvironment Promotes Pancreatic Cancer through miR-451a/MEF2D Axis

Pancreatic cancer (PC), as a highly malignant and aggressive solid tumor, is common in the digestive system. The acidic microenvironment is one of the critical markers of cancer. Nonetheless, there are few studies on how the acidic microenvironment affects the development of PC. This study focused on investigating the specific molecular mechanisms of the acidic microenvironment in PC. In our study, qRT-PCR was conducted for examining microRNA (miR)-451a and myocyte enhancer factor 2D (MEF2D) expressions in PANC-1 cells. Then, detailed functional effects of an acidic environment on miR-451a and MEF2D in PANC-1 cells were detected by CCK-8, colony formation, flow cytometry, wound healing, transwell, mitochondrial functionality measurement, JC-1 staining, DCFH-DA staining, and sphere formation assays. The relationship between miR-451a and MEF2D was confirmed by luciferase reporter analysis. Under acidic conditions, the increase of proliferation, migration, and invasion of PANC-1 cells was observed. Moreover, the mitochondrial oxidative respiration-related gene miR-451a was reduced in acidic conditions. In addition, we found that, in PANC-1 cells under an acidic environment, miR-451a overexpression enhanced oxygen consumption, mitochondrial membrane potential (MMP) loss, and ROS generation and inhibited proliferation, migration, invasion, and stemness via sponging MEF2D. In a word, our results revealed that the acidic microenvironment regulated PC progression by affecting the miR-451a/MEF2D axis, indicating a novel avenue for the future treatment of PC.

Midazolam Ameliorates Hyperglycemia-Induced Glomerular Endothelial Dysfunction by Inhibiting Transglutaminase 2 in Diabetes

Midazolam is an anesthetic widely used for anxiolysis and sedation; however, to date, a possible role for midazolam in diabetic kidney disease remains unknown. Here, we investigated the effect of midazolam on hyperglycemia-induced glomerular endothelial dysfunction and elucidated its mechanism of action in kidneys of diabetic mice and human glomerular microvascular endothelial cells (HGECs). We found that, in diabetic mice, subcutaneous midazolam treatment for 6 weeks attenuated hyperglycemia-induced elevation in urine albumin/creatinine ratios. It also ameliorated hyperglycemia-induced adherens junction disruption and subsequent microvascular leakage in glomeruli of diabetic mice. In HGECs, midazolam suppressed high glucose-induced vascular endothelial-cadherin disruption and endothelial cell permeability via inhibition of intracellular Ca2+ elevation and subsequent generation of reactive oxygen species (ROS) and transglutaminase 2 (TGase2) activation. Notably, midazolam also suppressed hyperglycemia-induced ROS generation and TGase2 activation in glomeruli of diabetic mice and markedly improved pathological alterations in glomerular ultrastructure in these animals. Analysis of kidneys from diabetic Tgm2−/− mice further revealed that TGase2 played a critical role in microvascular leakage. Overall, our findings indicate that midazolam ameliorates hyperglycemia-induced glomerular endothelial dysfunction by inhibiting ROS-mediated activation of TGase2.

Mechanistic Basis of Arsenic Induced Carcinogenesis: Differential miRNA Expression

Arsenic, a toxic metalloid, provokes many detrimental consequences to human health. It is prevalent in earth's crust and poses a major threat to humans globally. Inorganic arsenic exposure occurs mainly via drinking water or food and is metabolized in mammals to form organic metabolites/ end products. Chronic exposure to arsenic causes lung, skin and urinary bladder cancers and increases the risks of liver, kidney and prostate cancers. Arsenic-induced ROS generation, disturbances in several signaling pathways, DNA repair inhibition, chromosomal aberrations, and epigenetic changes including alterations in DNA methylation, histone modifications and differential miRNA expression profiles are involved in cancer progression, and malignant transformation. However, details of arsenic-induced carcinogenesis and molecular mechanisms involved are still remaining obscure. MicroRNAs are post-transcriptional gene expression regulators and themselves may act as oncogenes and tumor suppressor genes. Differential miRNA expression is implicated in several human cancers. This review covers general mechanistic basis of arsenic-induced carcinogenesis, explores recent in-vitro, in-vivo and cohort studies on differential miRNA expression profiles and shares associated molecular mechanistic data on miRNA dysregulation and their functional consequences leading to arsenic induced tumorigenesis, metastasis and cancer, also discusses the future directions.

NIR and Reduction Dual-Sensitive Polymeric Prodrug Nanoparticles for Bioimaging and Combined Chemo-Phototherapy

The combination of chemotherapy, photothermal therapy (PTT) and photodynamic therapy (PDT) based on a single nanosystem is highly desirable for cancer treatment. In this study, we developed a versatile Pt(IV) prodrug-based nanodrug, PVPt@Cy NPs, to realize synchronous chemotherapy, PDT and PTT and integrate cancer treatment with bioimaging. To construct PVPt@Cy NPs, the amphiphilic Pt(IV)-based polymeric prodrug PVPt was synthesized by a facile one-pot coupling reaction, and then it was used to encapsulate an optotheranostic agent (HOCyOH, Cy) via hydrophobic interaction-induced self-assembly. These NPs would disaggregate under acidic, reductive conditions and NIR irradiation, which are accompanied by photothermal conversion and reactive oxygen species (ROS) generation. Moreover, the PVPt@Cy NPs exhibited an enhanced in vitro anticancer efficiency with 808-nm light irradiation. Furthermore, the PVPt@Cy NPs showed strong NIR fluorescence and photothermal imaging in H22 tumor-bearing mice, allowing the detection of the tumor site and monitoring of the drug biodistribution. Therefore, PVPt@Cy NPs displayed an enormous potential in combined chemo-phototherapy.

Organic Nanoparticles Based on D-A-D Small Molecule: Self-Assembly, Photophysical Properties, and Synergistic Photodynamic/Photothermal Effects

Cancer is one of the major diseases threatening human health. Traditional cancer treatments have notable side-effects as they can damage the immune system. Recently, phototherapy, as a potential strategy for clinical cancer therapy, has received wide attention due to its minimal invasiveness and high efficiency. Herein, a small organic molecule (PTA) with a D-A-D structure was prepared via a Sonogashira coupling reaction between the electron-withdrawing dibromo-perylenediimide and electron-donating 4-ethynyl-N,N-diphenylaniline. The amphiphilic organic molecule was then transformed into nanoparticles (PTA-NPs) through the self-assembling method. Upon laser irradiation at 635 nm, PTA-NPs displayed a high photothermal conversion efficiency (PCE = 43%) together with efficient reactive oxygen species (ROS) generation. The fluorescence images also indicated the production of ROS in cancer cells with PTA-NPs. In addition, the biocompatibility and photocytotoxicity of PTA-NPs were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and live/dead cell co-staining test. Therefore, the as-prepared organic nanomaterials were demonstrated as promising nanomaterials for cancer phototherapy in the clinic.

Mechanistic Insights Expatiating the Redox-Active-Metal-Mediated Neuronal Degeneration in Parkinson’s Disease

Parkinson’s disease (PD) is a complicated and incapacitating neurodegenerative malady that emanates following the dopaminergic (DArgic) nerve cell deprivation in the substantia nigra pars compacta (SN-PC). The etiopathogenesis of PD is still abstruse. Howbeit, PD is hypothesized to be precipitated by an amalgamation of genetic mutations and exposure to environmental toxins. The aggregation of α-synucelin within the Lewy bodies (LBs), escalated oxidative stress (OS), autophagy-lysosome system impairment, ubiquitin-proteasome system (UPS) impairment, mitochondrial abnormality, programmed cell death, and neuroinflammation are regarded as imperative events that actively participate in PD pathogenesis. The central nervous system (CNS) relies heavily on redox-active metals, particularly iron (Fe) and copper (Cu), in order to modulate pivotal operations, for instance, myelin generation, synthesis of neurotransmitters, synaptic signaling, and conveyance of oxygen (O2). The duo, namely, Fe and Cu, following their inordinate exposure, are viable of permeating across the blood–brain barrier (BBB) and moving inside the brain, thereby culminating in the escalated OS (through a reactive oxygen species (ROS)-reliant pathway), α-synuclein aggregation within the LBs, and lipid peroxidation, which consequently results in the destruction of DArgic nerve cells and facilitates PD emanation. This review delineates the metabolism of Fe and Cu in the CNS, their role and disrupted balance in PD. An in-depth investigation was carried out by utilizing the existing publications obtained from prestigious medical databases employing particular keywords mentioned in the current paper. Moreover, we also focus on decoding the role of metal complexes and chelators in PD treatment. Conclusively, metal chelators hold the aptitude to elicit the scavenging of mobile/fluctuating metal ions, which in turn culminates in the suppression of ROS generation, and thereby prelude the evolution of PD.